Trash Tutorial: Some glass can be recycled, some not

Saturday

Apr 12, 2014 at 12:01 AM

Q: What happens with all the broken glass in those big recycle containers? Even though we are careful not to put any broken glass in with our household recyclables, the minute the stuff gets dropped into...

By Sarah Kite-Reeves

Q: What happens with all the broken glass in those big recycle containers? Even though we are careful not to put any broken glass in with our household recyclables, the minute the stuff gets dropped into the everything-in-one-container recycling bins at the transfer station, the glass gets broken and crushed, even double crushed as the attendant admitted, by the machine that crunches everything together. How is that a good idea, and what do they do with all the broken glass when it gets to the Central Landfill? There has to be a better solution.

— Dolores Lloyd

Narragansett

A: The main reason we tell residents that they shouldn’t put broken glass in their recycling bins is to protect sanitation workers. In curbside collection communities, if the service isn’t yet automated, a worker has to lift the bins by hand into the recycling truck. Occasionally, recyclables fall out of the bin. If broken glass is placed directly in the bin, the worker could be injured. In transfer station communities, there is less of a chance of injuries occurring, but they do happen.

The second reason is that some broken household glass isn’t container glass, and there’s a difference between household glass and food container glass, and it’s the food container glass that our customers want.

The two types of glass commonly found in a household are borosilicate glass and silicate glass. Borosilicate is better known as tempered glass, and is associated with the brand name Pyrex. This type of glass will typically splinter rather than shatter. It has a higher melting point than silicate glass, which is generally used for food containers, like pasta sauce, mustard jars, and beer and wine bottles.

Our sorting system can’t distinguish between the two common household glass types, so if it were all mixed together, our glass customers would be saddled with huge amounts of contamination. So, for now, only recycle glass food jars and bottles, and leave household product glass to the trash if broken. And again, for the safety of sanitation workers, if you do break a mixing bowl, light bulb, or drinking glass, please place the broken pieces in a cardboard box, tape the box closed, write “broken glass” on the box, and place it in the trash.